Fluidics head for testing chemical and ionic sensors

Abstract

A fluidics head to facilitate the automatic testing of chemical and ionic sensing electronic circuit devices is provided. The fluidics head comprises a fluid confining cell having an open orifice capable of containing a known test fluid while the orifice is in leakproof engagement with sensing electronic circuit devices, an inlet and outlet opening capable of filling and discharging test fluids, and electrical probes capable of contacting the sensing electronic circuit devices so as to test the electrical response of the devices with the test fluids.

What is claimed is: 
     
       1. A fluidics head or a multiplicity of heads in an array thereof for automatically testing chemical and ionic sensing electronic circuit devices comprising: a fluid confining cell having at least one open orifice to contain a known test fluid,   means for filling said test fluid into said open orifice and discharging said test fluid from said open orifice when said orifice is in leakproof engagement with said sensing electronic circuit device to be tested, and   means for providing electrical contacts to said sensing electronic circuit device so as to test said sensing electronic circuit device with said test fluid, wherein said open orifice has an internal shape such that fluid contamination in said fluid confining cell is minimized during discharge of said test fluid.   
     
     
       2. The fluidics head of claim 1 wherein said filling means comprises one inlet opening and one outlet opening in said fluid confining cell. 
     
     
       3. The fluidics head of claim 2 wherein the inlet opening and the outlet opening are at opposite ends of said confining cell. 
     
     
       4. The fluidics head of claim 2 wherein said open orifice is shaped so as to closely conform to the shape of said inlet and outlet openings. 
     
     
       5. The fluidics head of claim 1 wherein said fluid confining cell having at least one open orifice has an internal volume and geometry sufficient to ensure that bulk solution characteristics prevail during the testing of said sensing electronic circuit device. 
     
     
       6. The fluidics head of claim 1 wherein said fluid confining cell is shaped to prevent buckling when the open orifice of said fluid containing cell is urged into leakproof engagement with said sensing electronic circuit device to be tested. 
     
     
       7. The fluidics head of claim 6 wherein said fluid confining cell has a supportive structure which is wedge-like in shape with rounded outer edges to provide leakproof engagement with said sensing electronic circuit device to be tested. 
     
     
       8. The fluidics head of claim 1 wherein said fluid confining cell is formed from a material which is (a) chemically inert to the fluids used; (b) non-adsorptrve; (c) physically strong to provide controlled deformation and sealing and to resist buckling when urged against a circuit to be tested and during fluid flow; and (d) capable of providing air and fluid seal.